1. Field of the Invention
The present invention relates to a blocking oscillator adapted for switching inductive loads and more particularly to a hybrid blocking oscillator circuit capable of surviving 5,000 hours with over 90% reliability.
2. Description of the Prior Art
Electromagnetic fluid pumps are used for a wide variety of applications including supplying fuel to internal combustion engines. As a result they are required to operate over a wide range of temperatures and endure relatively large voltage fluctuations. Since the operation of the engine requires a dependable fuel supply for starting and continued operation, the fuel pump and its associated electronic circuitry must be reliable and trouble free.
Disclosed herein is an improved blocking oscillator of the type generally disclosed in my prior U.S. Pat. No. 3,629,674 (Dec., 1971) and H. P. Wertheimer et al., U.S. Pat. No. 3,381,616 (May, 1968) which has a higher tolerance to voltage fluctuations and a longer life than realized with the earlier blocking oscillators.